All matter is a cognitive ‘hallucination,’ even the brain itself

I think this relies on multiple ambiguous definitions of "hallucination." Just because we say that the brain hallucinates our experiences does not imply that there is no external world. Our internal experiences are hallucinations in the sense that they are not the external things themselves. But there may still be external things.

~~ Paul

Right, but the challenge is if we have a shared experience of reality it can still differ wildly from what is really out there. 

The "Is reality a hallucination?" question comes in because those experiences that are shared are regarded as real, though of course for the materialist the picture looks as Lehar draws it:



Which leads to the issue presented in the article. Or as the neuroscientist Smythies puts it, "How can the brain be in the head when the head is in the brain?"

[The article does seem to make a leap from this problem to the assertion Idealism is true, which feels rather unjustified.]

That said, "hallucination" does seem better used in reference to that which is distinctly not in the realm of shared experience, with the additional note that what is perceived seems "out of step" with the causal flow [of] said shared experience.

I think this relies on multiple ambiguous definitions of "hallucination." Just because we say that the brain hallucinates our experiences does not imply that there is no external world. Our internal experiences are hallucinations in the sense that they are not the external things themselves. But there may still be external things.

~~ Paul

The internal experience themselves cannot be "hallucination", as that makes no sense ~ but our internal experience of external experiences may well be. It just so happens that all humans happen to share the same set of "hallucinations".

Even our experience of matter and physics being the way it is is "hallucination".

The internal experience themselves cannot be "hallucination", as that makes no sense ~ but our internal experience of external experiences may well be. It just so happens that all humans happen to share the same set of "hallucinations".

Even our experience of matter and physics being the way it is is "hallucination".

I agree that at some point deep in the experience stack it doesn't make sense to say it's an hallucination. But it can certainly be the case that some internal experiences (i.e., experiences that are not of external events) are hallucinations. I think it's fair to say that an LSD trip is an hallucination.

Again, I think we're using the word "hallucination" in a loose manner.

~~ Paul

I agree that at some point deep in the experience stack it doesn't make sense to say it's an hallucination. But it can certainly be the case that some internal experiences (i.e., experiences that are not of external events) are hallucinations. I think it's fair to say that an LSD trip is an hallucination.

Again, I think we're using the word "hallucination" in a loose manner.

~~ Paul

Hmmmmm, are "hallucinations" illusions, or can some be real? Experiences of emotion, thoughts and beliefs are not of external events, though perhaps triggered by them. Are they thus "hallucination"?

What exactly is a "hallucination" anyways, if say during LSD a bunch of friends vegetating on a couch have unwitting telepathic conversations that they don't notice until they pay attention, and realize no-one's been vocalizing anything?

The word seems to be a bit vague in general, which is there are many different apparently uses of it. Everyone has their own definition.

Right, but the challenge is if we have a shared experience of reality it can still differ wildly from what is really out there. 

The "Is reality a hallucination?" question comes in because those experiences that are shared are regarded as real, though of course for the materialist the picture looks as Lehar draws it:



Which leads to the issue presented in the article. Or as the neuroscientist Smythies puts it, "How can the brain be in the head when the head is in the brain?"

[The article does seem to make a leap from this problem to the assertion Idealism is true, which feels rather unjustified.]

That said, "hallucination" does seem better used in reference to that which is distinctly not in the realm of shared experience, with the additional note that what is perceived seems "out of step" with the causal flow [of] said shared experience.

Our experience can differ wildly from what is out there only to the degree that other organisms have enough brain power to conjure up a different experience. Does a ragworm have enough brain power to invent something different from the actual external world? I don't think so. To fix this issue, we have to assume that the ragworm has no internal experience, or we have to assume that ragworms are just figments of our imagination and what's really out there is something wildly different from the perceived ragworms.

Wouldn't it be easier just to assume that the external world is pretty similar to our normal experience of it? The head is an external thing that contains a brain, which is also an external thing. Part of the processing performed by that brain gives us an exerperience of the brain, the head, and the rest of the world.

~~ Paul

Our experience can differ wildly from what is out there only to the degree that other organisms have enough brain power to conjure up a different experience. Does a ragworm have enough brain power to invent something different from the actual external world? I don't think so. To fix this issue, we have to assume that the ragworm has no internal experience, or we have to assume that ragworms are just figments of our imagination and what's really out there is something wildly different from the perceived ragworms.

Wouldn't it be easier just to assume that the external world is pretty similar to our normal experience of it? The head is an external thing that contains a brain, which is also an external thing. Part of the processing performed by that brain gives us an exerperience of the brain, the head, and the rest of the world.

~~ Paul

But we know at least some animals have interfaces that aren’t aligned with the real world, why you have beetles trying to mate with shiny glass shards?

We also know the subatomic world has characteristics we don’t expect at the macro-level.

If “processing” gives an experience, then we’re back to hallucinations since consciousness is then an illusion as well?

The internal experience themselves cannot be "hallucination", as that makes no sense ~ but our internal experience of external experiences may well be. It just so happens that all humans happen to share the same set of "hallucinations".

Even our experience of matter and physics being the way it is is "hallucination".

Yeah the materialists wanted consciousness to be an illusion, but still want there to be a world out there that the illusion is producing accurately...insofar as it agrees with the materialist belief system...

Very much a group that wants to enjoy eating and saving the cake at the same time...

Our experience can differ wildly from what is out there only to the degree that other organisms have enough brain power to conjure up a different experience. Does a ragworm have enough brain power to invent something different from the actual external world? I don't think so. To fix this issue, we have to assume that the ragworm has no internal experience, or we have to assume that ragworms are just figments of our imagination and what's really out there is something wildly different from the perceived ragworms.

This assumes that brains are the things "conjuring" experience... yet a major problem with this is that physics and chemistry proper have no ability to create abstractions, so no representations, metaphors, etc.

And besides that... what is an "actual external world"?

Wouldn't it be easier just to assume that the external world is pretty similar to our normal experience of it? The head is an external thing that contains a brain, which is also an external thing. Part of the processing performed by that brain gives us an exerperience of the brain, the head, and the rest of the world.

~~ Paul

So... you believe in naive / direct realism, nevermind all of the major flaws it has?

It cannot account for, or explain hallucinations of any kind, or any distortion of the senses, frankly.

https://plato.stanford.edu/entries/perception-problem/

2. The Problem of Perception

The Problem of Perception is that if illusions and hallucinations are possible, then perceptual experience, as we ordinarily understand it, is impossible. The Problem is animated by two central arguments: the argument from illusion (§2.1) and the argument from hallucination (§2.2). (A similar problem arises with reference to other perceptual phenomena such as perspectival variation or conflicting appearances: see Burnyeat (1979) and the entry on sense-data). For some classic readings on these arguments, see Moore (1905, 1910); Russell (1912); Price (1932); Broad (1965); and Ayer (1940), see Swartz (1965) for a good collection of readings. And for more recent expositions see Snowdon (1992), Valberg (1992), Robinson (1994: Chapter 2), Smith (2002: Chapters 1 and 7), Martin (2006), Fish (2009: Chapter 2), Brewer (2011: Chapter 1) and Pautz (2021).

The two central arguments have a similar structure which we can capture as follows:

1. In an illusory/hallucinatory experience, a subject is not directly presented with an ordinary object.
   
2. The same account of experience must apply to veridical experiences as applies to illusory/hallucinatory experiences.
   

Therefore,

1. Subjects are never directly presented with ordinary objects.
   

(C) contradicts Direct Realist Presentation, and thus our ordinary conception of perceptual experience. And since Direct Realism seems to follow from Direct Realist Presentation, the argument challenges Direct Realism too (for more on this see §3.2.6).

But we know at least some animals have interfaces that aren’t aligned with the real world, why you have beetles trying to mate with shiny glass shards?

We also know the subatomic world has characteristics we don’t expect at the macro-level.

If “processing” gives an experience, then we’re back to hallucinations since consciousness is then an illusion as well?

I agree that internal experience is sometimes closely aligned with the external world and sometimes not so closely aligned. But I'm not sure why that is a particularly important detail. It's just a question of the fidelity of the internal experience.

I don't know how to answer whether consciousness is an "illusion," because I am suspicious that we have different definitions of "hallucination," "illusion," etc.

~~ Paul

This assumes that brains are the things "conjuring" experience... yet a major problem with this is that physics and chemistry proper have no ability to create abstractions, so no representations, metaphors, etc.

And besides that... what is an "actual external world"?


So... you believe in naive / direct realism, nevermind all of the major flaws it has?

It cannot account for, or explain hallucinations of any kind, or any distortion of the senses, frankly.

https://plato.stanford.edu/entries/perception-problem/

I don't think you can just-so the claim that a physical brain has no ability to create abstractions. I have no idea why you would think this is the case.

I don't know what the external world is, except that there clearly is one. For example, when I go on holiday and return home, the trees in my yard are in the same place. That has nothing to do with my being conscious of them. They might not exist independently of my memory, but how could we know?

I don't think I'm a direct realist, since I agree that we perceive things filtered through some kind of internal model of the world that can hide or distort the things we perceive, or even invent something quite different. But this doesn't mean that our perception isn't usually more or less like the external things, and that it's possible to use instruments to make our perception closer, or to take something like a drug to make our perception more distorted.

~~ Paul